Voltage regulators are used in electronic equipment to supply a regulated voltage to a load. A switching-mode voltage regulator uses a pair of switches (e.g., control and sync MOSFET switches) to regulate the voltage output from the regulator. The switches are alternately turned on and off, and the regulated voltage is output from an energy storage device such as an inductor that is coupled between the switches.
Conventional switching-mode voltage regulators experience voltage spikes when the control MOSFET is turned on because the reverse recovery current of the body diode of the sync MOSFET allows excess current to flow when the sync MOSFET is turned off. Conventional approaches to deal with the voltage spikes include the use of a Schottky or fast recovery diode implemented on the body diode of the sync MOSFET to reduce reverse recovery current, the use of an R-C snubber, and the implementation of soft recovery on the body diode. However, these conventional approaches are relatively expensive and/or ineffective.